Add Reference List for "VitriniteMountTechnique"

VitriniteMountTechnique was identified as needing a reference list, but is currently free text.

Values have been identified and the list has been drafted at the link below

https://gitlab.opengroup.org/osdu/subcommittees/data-def/projects/RAFSDDMSDEV/docs/-/blob/main/Design%20Documents/ReferenceValues/Manifests/reference-data/OPEN/VitriniteMountTechnique.json

We also need to modify existing Vitrinite Reflectance content schema attribute 'VitriniteMountTechnique' to

        "VitriniteMountTechnique": {
            "type": "string",
            "description": "Preparation technique for vitrinite mount"
            "pattern": "^[\\w\\-\\.]+:reference-data\\-\\-VitriniteMountTechnique:[\\w\\-\\.\\:\\%]+:[0-9]*$"
        },